1. Field of the Invention
The invention relates to surgical clips and hemostat constructions therefor, for the purposes of ligating (closing off) blood vessels, nerves or other anatomical structures during a surgical or other medical procedure on a human being or other animal.
2. State of the Art
The conventional method for ligating blood vessels or other anatomical structures utilizes the tying off, with a thread, of the blood vessels or other structures. Since a surgical procedure can be characterized as a struggle against bleeding, quickness and certainty are important for sealing off the cut end of a blood vessel. It is also always desirable to make any surgical procedure as brief as possible for the convenience of the patient and the economical use of the time of medical personnel and facilities. The string ligation technique is undesirable, because of the time which it takes, the requirement that two persons be involved in the ligation procedure and the sometime difficulty of access to remote anatomical locations for string ligating.
Some surgeons have adopted the use of metal clips in lieu of such string ligation procedures. Metal clips of th type most commonly used currently are disclosed and illustrated in U.S. Pat. No. 3,363,628, and an applicator construction illustrating a method of application of such a metal clip is illustrated in U.S. Pat. No. 3,326,216.
Other types of metal clip constructions are illustrated in U.S. Pat. Nos. 3,270,745, 3,347,239, 3,867,944 and 3,439,522. Still other types of clips and applications therefor are illustrated in U.S. Pat. Nos. 3,954,108, 3,882,854, 3,924,629 and 3,856,016.
Although the commonly used metal clips comprise, in some respects, an advance over the prior art of ligation they do possess several substantial disadvantages. The metal clips are quite small, on the order of 3 mm. or more in length, and are difficult to handle. A primary disadvantage is the inconvenience of and time consumed in placing the clip in the applicator and placing the clip over the blodd vessel before closure. Also, metal clips occasionally drop into the surgical opening and may be difficult to locate and remove.
One shortcoming of the prior art use of small metal clips may be understood by the analogy of attempting to thread a needle having a small eye. It is difficult to get the thread through the needle because of the size of the eye. Similarly, the U-shape of the surgial clips of the prior art and their extremely small size and opening makes it difficult to get the clip accurately placed in proper position over the blood vessel before closure. This difficulty means that the use of the clips of the prior art is relatively time-consuming and therefore undesirable because of the timportance of shortening the duration of surgery as much as possible.
The instant invention, when compared to the prior art, may be analogized to the use of a needle with a large eye being threaded with the same piece of thread. The large eye facilitates the insertion of the thread therethrough. Similarly, the fastening of the inserts (sometimes also referred to as clip assembly members) to hemostat jaws provides a greater opening for movement with respect to the structure being ligated.
An important advantage of this invention is that it reduces the ligation procedure from two steps to one step, since the placing of the hemostat over the blood vessel to close off flow in the blood vessel automatically closes and locks the clip members in place, so that when the hemostat is opened up and removed the clip is automatically left in place, avoiding the necessity of a second step to place a metal clip in place or to otherwise ligate the vessel.